Tribal Court Jurisdiction and Public Law 280: What Role for Tribal Courts in Alaska

GPS data from Challenging Mini-satellite Payload (CHAMP) is used for its orbit determination for the epoch day of January 1st 2002.  The orbit of CHAMP is computed from the GPS data and ionospheric effects are removed by frequency combination. Further, the orbits of CHAMP for the same epoch day are computed using the satellite tool kit (STK) employing simplified general perturbations (SGP4) and a high precision orbit propagator (HPOP). Furthermore, orbits computed using GPS data are also compared with jet propulsion laboratory’s published CHAMP spacecraft orbit and we have found that root mean square difference in ECEF position X component is below 0.01km other than some spikes at poles. The standard deviation of the difference in ECEF position X coordinate (JPL results – GPS computed results) is 11.7m. Since JPL computed orbits are considered as true orbits of CHAMP with accuracy of centimeter level (https://gipsy-oasis.jpl.nasa.gov/). Therefore this difference can also be referred as observed error in GPS computed orbits. Considering above discussion, we can expect that accuracy of our computed satellite positions (using GPS data) is about 12 metres for other than poles area. However there are some occasional spikes, especially at poles, having maximum errors (about 0.055 km)

GPS Data Processing Software

Práce se zabývá návrhem a implementací aplikace pro zpracování údajů o prošlých trasách ve formátu GPX. Aplikace zobrazuje trasu na mapových podkladech, umožňuje její editaci, pojmenování trasových bodů a přiřazení fotografií. O trase poskytuje řadu statistických údajů včetně grafů výškového a rychlostního profilu. Aplikace také nabízí možnost sestavit a vygenerovat prezentaci obsahující fotografie a snímky mapy. Teoretická část práce pojednává o systému GPS, způsobu záznamu trasy, o mapových podkladech a o návrhu aplikace. Cílem praktické části je pak navržené řešení implementovat a otestovat.The aim of the thesis is to suggest and implement an application for processing data about absolved tracks in GPX format. The application displays tracks on map layers, offering the possibility of editing the tracks, naming points on the tracks and adding photographs. A whole scale of statistic data is available for each track, including elevation and speed profile graph. Moreover, the application enables users to prepare and generate a presentation including photographs and map screenshots. The theoretical part of the thesis deals with GPS navigation system, ways of recording routes (tracks), map data and application suggestion. The aim of the practical part is to implement the suggested solution and test it.

Height determination using GPS data, local geoid and global geopotential models

Orthometric heights are normally derived using the spirit levelling. This requires the spirit level equipment to be set up from point 10 point along a levelling line which is a time consuming and tedious task. GPS offers a new altematiV)O in orthometric height determination very accurately over a comparatively short period. The ellipsoidal height derived from GPS technique can be transformed into orthometric height if we know the geoidal height normally derived from a gravimetric geoid of the area. Unfortunately, we have yet to compute an accurate gravimetric geoid for such purpose, largely due to nonexistence of gravity data for a larger part of the Country. As an alternative, a study was undertaken to look into the feasibility of using a simple local geoid solution and a global geopotential geoid model solution The data used in this study consist of GPS data and known orthometric height ofseveral GPS points. This paper present some of the results obtained so far in estimating orthometric height from GPS data in local en,ironment

Investigating the mobility habits of electric bike owners through GPS data

This paper investigates the mobility habits of electric bike owners as well as their preferred routes. Through a GPS tracking campaign conducted in the city of Ghent (Belgium) we analyze the mobility habits (travel distance, time spent, speed) during the week of some e-bike users. Moreover, we propose the results of our map matching, based on the Hausdorff criterion, and preliminary results on the route choice of our sample. We strongly believe that investigating the behavior of electric bikes’ owners can help us in better understanding how to incentivize the use of this mode of transport. First results show that the trips with a higher travel distance are performed during the working days. It could be easily correlated with the daily commuting trips (home-work). Moreover, the results of our map-matching highlight how 61% of the trips are performed using the shortest path